N.H. Admin. Code § Env-Ws 364.03
As used in this part, unless the content clearly indicates otherwise, the following words shall have the following meanings:
(a) "Air gap" means an unobstructed vertical distance equal to twice the diameter of the supply pipe or supply faucet or one inch, whichever is greater, through the free atmosphere between the lowest opening from any pipe or faucet supplying water to a tank, plumbing fixture, or other device and the flood level rim of the receptacle.
(b) "Approved backflow prevention device" means a backflow prevention device that has been:
(1) Manufactured to allow for accurate testing and inspection so as to allow verification of performance; and
(2) Tested and certified by the University of Southern California, Foundation for Cross-Connection Control and Hydraulic Research.
(c) "Approved source" means a source of water used by a public water system for distribution to the public for consumptive purposes which has been approved by the department for said use.
(d) "Backflow" means the flow of unwanted substances into the water distribution pipes of a potable supply of water.
(e) "Backflow prevention device" means a device that is designed to, and which in practice does, prohibit unwanted substances from flowing into the water distribution pipes of a potable supply of water.
(f) "Backflow prevention device with intermediate atmospheric vent" means a backflow prevention device having 2 independently-operating check valves separated by an intermediate chamber, with a means for automatically venting the intermediate chamber to the atmosphere.
(g) "Back pressure" means pressure created by mechanical means or other means causing water or other liquids or substances to flow or move in a direction opposite to what is intended.
(h) "Back-siphonage" means a backflow resulting from negative or reduced pressure in the water distribution pipes of a potable water supply.
(i) "Barometric loop" means a loop of pipe rising at least 35 feet at its topmost point above the highest fixture it supplies and which provides protection from back-siphonage only.
(j) "Certified backflow prevention device inspector" means an individual who has proven his or her competency to inspect and test backflow prevention devices, by the possession of a valid backflow prevention device certification issued by the New England Water Works Association.
(k) "Check valve" means a self-closing device which is designed to permit the flow of fluids in one direction and to close if there is a reversal of flow.
(l) "Contaminant" means "contaminant" as defined in RSA 485:1-a, II, namely "any physical, chemical, biological or radiological substance or matter in the water".
(m) "Containment" means that method and philosophy of backflow prevention which requires a backflow prevention device to be installed at the water service entrance.
(n) "Cross-connection" means any actual or potential physical connection or arrangement between 2 otherwise separate systems, one of which contains potable water and the other which contains water of unknown or questionable safety or steam, chemicals, gases, or other contaminants, whereby there may be a flow of unwanted substances into the potable water supply system.
(o) "Customer or property owner" means any person who has legal title to or license to operate or inhabit a property at which a cross-connection inspection is to be made or at which a cross-connection is present.
(p) "Department" means the department of environmental services.
(q) "Double check valve" means a device incorporating 2 spring-loaded check valves within a single unit, having 2 shut-off valves and the necessary appurtenances for testing.
(r) "High degree of hazard" means that if a backflow were to occur, the resulting effect on the potable water supply could cause illness or death if the water thus contaminated were consumed by humans. The unwanted substance may be toxic to humans either from a chemical, bacteriological, or radiological standpoint. The effects of the contaminants can result from short or long-term exposure.
(s) "Low degree of hazard" means that if backflow were to occur, the resulting effect on the potable water supply would be a change in its aesthetic qualities only and the unwanted substance is non-toxic to humans.
(t) "Person" means "person" as defined in RSA 485:1-a, XIII, namely "any individual, partnership, company, public or private corporation, political subdivision or agency of the state, department, agency or instrumentality of the United States or any other legal entity."
(u) "Potable water" means water from a source which has been approved by the department for human consumption.
(v) "Pressure vacuum breaker" means a device with an internally spring-loaded check valve and a spring-loaded air inlet valve, having 2 shut-off valves and the necessary appurtenances for testing, designed to operate under constant pressure but not back pressure.
(w) "Public water system" means public water system as defined in RSA 485:1-a, XV.
(x) "Reduced pressure backflow device" means a device incorporating 2 or more spring-loaded check valves and an automatically-operating relief valve located between the 2 check valves, with 2 shut-off valves and the necessary appurtenances for testing.
(y) "Residential dual check valve" means a device, designed for backpressure and back-siphonage protection for residential dwellings, which incorporates 2 spring-loaded check valves in a single unit without shut-off valves or testing appurtenances in accordance with American Society of Sanitary Engineers (ASSE) Standard 1024.
(z) "Supplier" means any person who controls, owns, or generally manages a public water supply system.
(aa) "Unwanted substances" means water or other liquids, gases, mixtures, or other substances from any source(s) other than the approved source(s) of water.
N.H. Admin. Code § Env-Ws 364.03
(See Revision Note at chapter heading for Env-Ws 300) #6521, eff 6-4-97; ss by #8360, INTERIM, eff 6-4-05, EXPIRES: 12 -1-05 ; ss by #8476, eff 11-30-05